Fortification of Foods with Folic Acid — How Much is Enough?

Abstract

In the early 1990s two randomized clinical trials showed that folic acid, or multivitamins containing folic acid, could substantially reduce a woman's risk of bearing a child with a neural-tube defect, provided that the vitamins were taken before conception.^1,2 In 1992 the Public Health Service recommended that all women of childbearing age who are capable of becoming pregnant consume 400 μg of folic acid daily.³ Not surprisingly, in a country where half the women who become pregnant each year are not planning to do so, compliance with this recommendation has been poor.⁴ At the time the recommendation was made, we . . .